CD4 and viral infectious disease: In viral infections, SARS-CoV-2, hCoV-229E, or HIV activate Panx1 hemichannels via CD4/CXCR4 CD4/CCR5, causing an outflow of ATP, which induces the maturation of IL-1ß through the activation of P2X7 receptors (Orellana et al., 2013a; Luu et al., 2021) (Figure 1B).